Vulnerability · Published Jun 17, 2026 · Assigned by VulnCheck

CVE-2026-53870Hermes Agent < 0.16.0 - Sensitive File Permission Vulnerability in Store Files

Medium 5.5

In plain English

A medium-severity incorrect default permissions in hermes-agent from NousResearch. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.5Medium

Exploit odds (30 days)0.2%top 94.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Hermes Agent before 0.16.0 creates response_store.db and webhook_subscriptions.json with world-readable permissions (mode 0o644), exposing conversation history and HMAC secrets to local users. Attackers with local filesystem access can read these files directly to obtain sensitive data including conversation history, tool payloads, prompts, and per-route HMAC secrets.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	hermes-agent	0.16.0	GHSA-99f9-j8r3-p853
PyPI	hermes-agent	0.16.0	PYSEC-2026-2511

Affected products (as reported)

Vendor	Product	Versions
NousResearch	hermes-agent	0 – before 0.16.0

Weakness: CWE-276 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

References

Release Notes release-notes
Researcher Pull Request issue-tracking
Maintainer Pull Request issue-tracking
Patch Commit patch
https://www.vulncheck.com/advisories/hermes-agent-sensitive-file-permission-vulnerability-in-store-files third-party-advisory